Cardiac surgery is associated with risk of perioperative inflammation and ischemia leading to cerebral and myocardial morbidity and mortality. Ischemic preconditioning by repetitive ischemic episodes at an organ can reduce damage resulting from consecutive prolonged ischemia in that organ. Remote ischemic preconditioning is defined as ischemic preconditioning by repetitive ischemic episodes of an organ remote from the organ to be protected, e.g. ischemic episodes of a limb can reduce ischemic damage of the heart. Animal studies as well as human studies have shown that ischemic preconditioning can protect the heart from intraoperative ischemia. Remote preconditioning by repetitive limb ischemia has been applied in humans in some studies.12-14 However, the published data is not yet sufficient to support evidence based recommendations for clinical practice. In particular, available data regarding the influence of remote preconditioning on inflammatory and ischemic damage of brain and heart in children following surgery of congenital heart disease are limited. Hence, this prospective, controlled and randomized study was designed to perform remote ischemic preconditioning in children after induction of anesthesia for pediatric heart surgery and to investigate the effect on postoperative organ function in comparison to a control group.